Pivotal Unit For Barbell

ABSTRACT

A barbell includes a rod and two tubular members are respectively mounted to the two ends of the rod. Two pivotal units are respectively located in the two tubular members and mounted to the two ends of the rod. Each pivotal unit has a washer, a bearing, a sleeve and a positioning member. The washer has a recess defined in one side thereof. The bearing is securely connected to the inside of the tubular member and a first end of the bearing contacts the washer. The sleeve is located in the bearing and securely mounted to the rod, a first end of the sleeve is movably engaged with the recess of the washer. The positioning member is a U-shaped manner and engaged with a groove defined in the rod. The positioning member contacts two respective seconds of the sleeve and the bearing.

FIELD OF THE INVENTION

The present invention relates to a barbell, and more particularly, to apivotal unit for a barbell.

BACKGROUND

The conventional barbell is used for weight training and generallycomprises a rod with two pivotal units mounted to two ends of the rod.Multiple weights are removably connected to the two pivotal units. Theuser grabs the center of the rod and lifts the barbell to train themuscles. The pivotal units ensure that the weights are automaticallyadjusted to a balance status relative to the rod so that the user doesnot need to rotate the rod by his/her wrists and this action can easilyinjure the wrists.

FIGS. 7 and 8 disclose the conventional barbell and the rod 70 withproper flexibility and two pivotal units 80 are mounted to two ends ofthe rod 70. Each of the two ends of the rod 70 has a groove 71. A needleroller bearing 72, a first ring 73, two positioning members 74, a secondring 75, two clips 76 and an end piece 77 are mounted to the rod 70 andlocated in the opening 81 of the tubular member of the pivotal unit 80.The two positioning members 74 are engaged with the groove 71. The firstring 73 contacts one end of the needle roller bearing 72 and the otherend of the needle roller bearing 72 is in contact with a shoulder 82 inthe tubular member. By the needle roller bearing 72, the rod 70 isrotatable relative to the tubular member of the pivotal unit 80. Thesecond ring 75 contacts the positioning members 74, and one of the clips76 contacts the second ring 75. By the positioning members 74, thetubular member does not moved relative to the rod 70. The end piece 77is cooperated with the other clip 76 to seal the end of the barbell.

However, because the material of the needle roller bearing 72 is harderthan that of the rod 70, so that when the rod 70 is rotatable relativeto the needle roller bearing 72, the rod 70 is worn by the frictionbetween the needle roller bearing 72 and the rod 70. Besides, when theuser puts the barbell to the floor, the impact also makes the rod 70 byworn out by the needle roller bearing 72. The pivotal unit 80 eventuallycannot rotate smoothly relative to the rod 70.

The two positioning members 74 are difficult to be engaged with thegroove 71 of the rod 70 when assembling the barbell. There is not properpositioning design to position the two positioning members 74 so thatthe assembling processes take a longer time.

There are too many parts involved in the pivotal unit and the clips 76are thin and not strong enough so that they are easily deformed and thepivotal unit 80 may shift along the rod 70.

The present invention intends to provide a barbell which improves theshortcomings mentioned in the conventional barbell.

SUMMARY OF THE INVENTION

The present invention relates to a barbell and comprises a rod havingtwo grooves respectively defined in two ends thereof and two tubularmembers are respectively mounted to the two ends of the rod. Two pivotalunits are respectively located in the two tubular members and mounted tothe rod. Each pivotal unit has a washer, a bearing, a sleeve, and apositioning member. The washer has a recess defined in one side thereof.The bearing is securely connected to the inside of the tubular member,and a first end of the bearing contacts the washer. The sleeve issecurely mounted to the rod and located in the bearing, and it first endof the sleeve is movably engaged with the recess of the washer. Thepositioning member is a U-shaped member and has an opening. Thepositioning member is connected to the rod and engaged with the groovevia the opening. The positioning member contacts two respective secondsof the sleeve and the bearing.

Alternatively, the present invention provides a barbell and comprises arod having two grooves respectively defined in two ends thereof. Twotubular members are respectively mounted to the two ends of the rod.Each tubular member has two open ends. Two pivotal units arerespectively located in the two tubular members and each pivotal unithas a self-lubricating sleeve and a positioning member. Theself-lubricating sleeve is mounted to the rod. The positioning member isa U-shaped member and has an opening. The positioning member isconnected to the rod and engaged with the groove via the opening. Thepositioning member contacts the self-lubricating sleeve.

The pivotal unit has a sleeve which is securely mounted to the rod andlocated within the bearing, the bearing and the sleeve are made byharder material when compared with that of the rod. Therefore, thanks tothe sleeve mounted to the rod, the rod is not worn by the nearing whenthe rod together with the sleeve are rotatable relative to the bearing.The bearing and the sleeve can also be replaced by a self-lubricatingsleeve.

The number of the parts of the pivotal unit of the present invention isreduced so that the barbell can be assembled quickly.

The present invention will become more obvious from the followingdescription when taken in connection with the accompanying drawingswhich show, for purposes of illustration only, a preferred embodiment inaccordance with the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view to show the barbell of the presentinvention;

FIG. 2 is an exploded view to show the barbell of the present invention;

FIG. 3 is a cross sectional view of the barbell or the presentinvention;

FIG. 4 is an enlarged cross sectional view of the pivotal unit of thebarbell of the present invention;

FIG. 5 is an enlarged cross sectional view to show the sleeve, and therecess of the washer of the pivotal unit of the barbell of the presentinvention;

FIG. 6 is an enlarged cross sectional view of the second embodiment ofthe pivotal unit of the barbell of the present invention;

FIG. 7 is an exploded view to show the conventional barbell, and

FIG. 8 is a cross sectional view of the conventional barbell.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring to FIGS. 1 to 3, the barbell 1 of the present inventioncomprises a rod 10 with proper flexibility and two grooves 11 arerespectively defined in two ends of the rod 10. Two tubular members 20are respectively mounted to the two ends of the rod 10 and the weights12 are mounted to the tubular members 20. Each tubular member 20 has twoopen ends 21 and a stop 13 is connected to the end away from the distalend of the rod 10 so as to position the weights 12.

Two pivotal units 30 are respectively located in the two tubular members20 and mounted to the two ends of the rod 10. Each pivotal unit 30 has awasher 31, a bearing 32, a sleeve 33, a positioning member 34 and an endpiece 35. The rod 10 extends through the two tubular members 20 and ashoulder 22 is formed in the inner periphery of each of the two openends 21 of the tubular member 20. The washer 31 has a recess 311 definedin one side thereof. The bearing 32 is securely connected to the insideof the tubular member 20, and a first end of the bearing 32 contacts thewasher 31 which contacts against the shoulder 22. The sleeve 33 issecurely mounted to the rod 10 and located in the bearing 32 whichdirectly contacts the sleeve 33 instead of the rod 10. The A first endof the sleeve 33 is movably engaged with the recess 311 of the washer 31as shown in FIGS. 4 and 5. The positioning member 34 is a U-shapedmember and has an opening 341. The positioning member 34 is connected tothe rod 10 and engaged with the groove 11 via the opening 341. Thepositioning member 34 contacts two respective seconds of the sleeve 33and the bearing 32. One of the two ends of the rod 10 extends beyond thepositioning member 34 and the end piece 35 is mounted to the end of therod 10 and connected to the open end 21 of the tubular member 20. Theend piece 35 contacts the positioning member 34 so as to position thepivotal unit 30 along the axial direction thereof.

It is noted that another pivotal unit 30 are located in the inner end ofeach tubular member 20, wherein the inner end is located away from theend piece 35 and cooperated with the stop 13, so that the pivotal unit30 in the inner end of the tubular member 20 comprises the bearing 32,the sleeve 33 in the bearing 32 and the washer 31 the recess 311.

The sleeve 33 is made by the same material as the bearing 32, and thesleeve 33 is securely mounted to and co-rotated with the rod 10, so thatwhen the rod 10 is rotatable relative to the bearing 32, the rod 10 isprotected from being worn out by the bearing 32. The recess 311 providesa space for the sleeve 33 so that the sleeve 33 is not securelyrestricted by the washer 31 and the positioning member 34 from the twoends thereof, and the sleeve 33 is rotatable relative to the bearing 32.

The positioning member 34 is a single member which can be easily andquickly engaged with the groove 11 of the rod 10 by the opening 341.This allows the assemblers to quickly assemble the barbell. The bearing32 is ensured not to move axially by the washer 31 and the positioningmember 34. The end piece 35 is connected to the open end 21 to thetubular member 20 and the end piece 35 contacts the positioning member34 so that the pivotal unit 30 is well positioned.

FIG. 6 shows the second embodiment of the pivotal unit 300 whichcomprises a self-lubricating sleeve 330 and a positioning member 34only. The self-lubricating sleeve 330 is mounted to the rod 10 and thepositioning member 34 contacts the self-lubricating sleeve 330. The endpiece 35 is connected to the open end 21 of the tubular member 20 andcontacts the positioning member 34 so that the pivotal unit 30 is wellpositioned. The self-lubricating sleeve 330 and the tubular member 30are rotatable relative to the rod 10 without the need of the sleeve asmentioned in the previous embodiment.

While we have shown and described the embodiment in accordance with thepresent invention, it should be clear to those skilled in the art thatfurther embodiments may be made without departing from the scope of thepresent invention.

What is claimed is:
 1. A barbell comprising: a rod having two groovesrespectively defined in two ends thereof, two tubular membersrespectively mounted to the two ends of the rod, each tubular memberhaving two open ends, and two pivotal units respectively located in thetwo tubular members and mounted to the two ends of the rod, each pivotalunit having a washer, a bearing, a sleeve and a positioning member, thewasher having a recess defined in one side thereof, the bearing beingconnected to the tabular member, a first end of the bearing contactingthe washer, the sleeve securely mounted to the rod and located in thebearing, a first end of the sleeve being movably engaged with the recessof the washer, the positioning member being a U-shaped member and havingan opening, the positioning member connected to the rod and engaged withthe groove via the opening, the positioning member contacting tworespective seconds of sleeve and the bearing.
 2. The barbell as claimedin claim 1, wherein the rod extends through the two tubular members andas shoulder is formed in an inner periphery or each of the two open endsof the tubular member, the washer contacts the shoulder.
 3. The barbellas claimed in claim 1, wherein one of the two ends of the rod extendsbeyond the positioning member and an end piece is mounted to the end ofthe rod and connected to the open end of the tubular member, the endpiece contacts the positioning member.
 4. A barbell comprising: a rodhaving two grooves respectively defined in two ends thereof, two tubularmembers respectively mounted to the two ends of the rod, each tubularmember having two open ends, and two pivotal units respectively located,in the two tubular members and mounted to the two ends of the rod, eachpivotal unit having a self-lubricating sleeve and a positioning member,the self-lubricating sleeve mounted to the rod, the positioning memberbeing a U-shaped member and having an opening, the positioning memberconnected to the rod and engaged with the groove via the opening, thepositioning member contacting the self-lubricating sleeve.
 5. Thebarbell as claimed in claim 4, wherein the rod extends through the twotubular members and a shoulder is formed in an inner periphery of eachof the two open ends of the tubular member, the self-lubricating sleevecontacts the shoulder.
 6. The barbell as claimed in claim 4, wherein oneof the two ends of the rod extends beyond the positioning member and anend piece is mounted to the end of the rod and connected to the open endof the tubular member, the end piece contacts the positioning member.